Phytodietus (Phytodietus) xui Kostro-Ambroziak & Reshchikov, 2020

Kostro-Ambroziak, Agata, Zhou, Zichen & Reshchikov, Alexey, 2020, A new species of Phytodietus Gravenhorst, 1829 (Hymenoptera: Ichneumonidae: Tryphoninae) from China, Zootaxa 4877 (2), pp. 391-395 : 392-394

Phytodietus (Phytodietus) xui Kostro-Ambroziak & Reshchikov sp. n.

( Figs 1–6 )

Material examined. Holotype ♀, CHINA, Yunnan, Shangri La , 3100m., 15.VIII.1983, leg. Dazhi Dong, ( KIZ).

Etymology. The species named after Prof. Zaifu Xu (SCAU).

Diagnosis. Phytodietus xui has a similar colour pattern to P. belokobylskii Kasparyan, 2016 from South Korea and P. dauricus Kasparyan, 2016 from Russia (Transbaikal Territory). It can be easily distinguished from the former species by its strongly shagreened face which is polished and very finely punctate centrally in P. belokobylskii , and from the latter species by having more flagellomeres (34-segmented flagellum in P. xui as opposed to 27-segmented in P. dauricus ). Compared to other Chinese species of Phytodietus which generally have a black body, P. xui is easy to discriminate by its rufous metapleuron and rufous mark on mesopleuron ( Fig. 6 ).

Description. Female (holotype). Body length 7.2 mm.

Head ( Figs 1–2 ). Face 0.68 times as high as wide, matt, strongly shagreened, especially on convex median area. Clypeus finely shagreened, with a basal transverse convexity and inclined apex. Apical half of clypeus trapezoidal, apical margin truncate with a weak but broad notch centrally. Upper tooth of mandible slightly longer than lower tooth. Malar space 0.5 times as long as basal width of mandible. Occipital carina complete, its lower end joining hypostomal carina. Temple roundly narrowed behind eye. Antenna with 34 flagellomeres; flagellomeres 1 to 4 unspecialized, not broader than distal ones.

Mesosoma matt, shagreened and with short, relatively dense setae. Pronotum without wrinkles; epomia absent. Mesoscutum 1.26 times as long as wide. Notauli distinctly impressed, present anteriorly and reaching backwards to level of tegulae in lateral view. Mesopleuron strongly shagreened, with nearly invisible punctures; speculum smooth and polished, without setae or punctures. Epicnemial carina distinct, present ventrally and laterally. Metapleuron shagreened, without wrinkles or visible punctures. Submetapleural carina complete, expanded anteriorly into a lobe. Pleural carina absent. Propodeum ( Fig. 3 ) matt, without transverse wrinkles, crests, or a longitudinal groove.

Wings ( Fig. 4 ). Forewing length 6.2 mm. Marginal cell 0.33 times as long as wide; areolet present; distance between 2 rs-m and 2 m-cu 1.08 times length of 2 rs-m; M distinct; cu-a inclivious, slightly postfurcal to Rs&M. Hind wing length 4.6 mm. All hind wing veins complete; first abscissa of Cu 1 longer than cu-a and joining cu-a at an angle.

Legs. Hind femur 5.6 times as long as wide. Hind tibia with rather strong bristles. Lateral spur of hind tibia 0.60 times as long as first metatarsus. Hind fifth tarsomere 0.67 times as long as third.

Metasoma ( Fig. 5 ). Tergites matt, with short moderately dense pubescence. First metasomal tergite 1.3 times as long as posteriorly wide; evenly tapered from base to apex, without a constriction between base and spiracle. Median basal pit of first tergite deep; median dorsal carinae present around basal pit. Dorsolateral edge of first tergite rounded for its entire length. Second tergite 0.7 times as long as anteriorly wide and 0.5 times as long as posteriorly wide.

Colouration ( Figs 1–6 ). Head predominantly black with following parts yellow: median part of clypeus, mandible (except for brown teeth), small marks on frons, inner margin of eyes. Antenna black. Mesosoma black apart from: small marks on pronotum and mesopleuron (both below tegula), elongate marks along anterolateral margin of mesoscutum, tegula, apical part of scutellum and postscutellum which are marked with yellow; and large irregular mark on mesopleuron, metapleuron, sides of propodeum which are rufous. Fore and mid legs dark yellow. Hind leg: coxa rufous with yellow apex, trochanter, trochantellus and femur dark yellow, tibia narrowly at base and 1/3 at apex blackish, the remainder dirty yellow, tibia black. Wings hyaline. First metasomal tergites black, second and following tergites black with narrow apical and lateral yellow bands. Ovipositor sheath black.

Male. Unknown.

Distribution. China: Yunnan.

Figures

FIGURES 1-6. Holotype of Phytodietus xui sp. nov., female. 1. Head, (facial view); 2. Head, (dorso-posterior view); 3. Propodeum, (dorsal view); 4. Wings; 5. First and second tergites of metasoma, (dorsal view); 6. Habitus, (lateral view).